Which term corresponds to the concentration that prevents visible growth of bacteria in a standard assay?

Which term corresponds to the concentration that prevents visible growth of bacteria in a standard assay?

• A. Bacteriostatic
• B. Bactericidal
• C. Kirby-Bauer Test
• D. Minimum Inhibitory Concentration (MIC)

Answer: (D)

The concentration that prevents visible growth in a standard antimicrobial susceptibility assay is the Minimum Inhibitory Concentration. In practice, you test a series of antimicrobial dilutions with a standardized amount of bacteria and incubate. The lowest concentration that shows no visible growth or turbidity is the MIC. This value reflects inhibition of growth, not necessarily killing the bacteria. It’s different from bacteriostatic, which describes the action of inhibiting growth, and bactericidal, which refers to killing bacteria. The Kirby-Bauer disk-diffusion method measures zones of inhibition rather than an MIC, and the actual concentration that kills bacteria is called the minimum bactericidal concentration.

The concentration that prevents visible growth in a standard antimicrobial susceptibility assay is the Minimum Inhibitory Concentration. In practice, you test a series of antimicrobial dilutions with a standardized amount of bacteria and incubate. The lowest concentration that shows no visible growth or turbidity is the MIC. This value reflects inhibition of growth, not necessarily killing the bacteria. It’s different from bacteriostatic, which describes the action of inhibiting growth, and bactericidal, which refers to killing bacteria. The Kirby-Bauer disk-diffusion method measures zones of inhibition rather than an MIC, and the actual concentration that kills bacteria is called the minimum bactericidal concentration.